ocaml-opam-tinyflags-add-flag

name	ocaml-opam-tinyflags-add-flag
description	Add a TinyFlags flag to an OCaml project with implementation, tests, and rollout notes.

Add TinyFlags Flag

Use this skill when adding a feature flag to an OCaml project that depends on agentxm-example-tinyflags.

Workflow

1. Find the OCaml module that constructs the Tinyflags.t flag set from a (name, flag) list (typically lib/<pkg>/flags.ml or similar).
2. Add the flag as either a Boolean (Tinyflags.Bool.make_exn ...) or a VariantFlag (Tinyflags.Variant.make_exn ...) entry.
3. Prefer kebab-case flag names that mirror the call-site behavior.
4. Add or update alcotest coverage in test/ for default behavior and rollout behavior. Run via dune runtest or dune exec ./test/<name>.exe.
5. Update the package's README or .opam description when the flag is user-facing.

Boolean Flags

Use Tinyflags.Bool.make_exn ~default:false () for a disabled-by-default feature.

Use Tinyflags.Bool.make_exn ~default:false ~rollout:10 () for a percentage rollout. Rollout bucketing is deterministic on the Tinyflags.Context.t [id] field — thread a stable identifier (user, session, account) through the request boundary.

Variant Flags

Use Tinyflags.Variant.make_exn ~default:"classic" ["classic"; "semantic"] when the call site needs a named treatment instead of true / false.

Use ~rollout to allocate traffic:

Tinyflags.Variant.make_exn
  ~default:"classic"
  ~rollout:[ ("semantic", 10) ]
  [ "classic"; "semantic" ]

Done Criteria

• New flag has an explicit ~default argument (boolean) or ~default argument (variant) tied to a member of the variant list.
• Rollout percentage is an int in 0..100.
• Variant rollout pairs reference only declared variants.
• alcotest cases cover default behavior and at least one rollout boundary.
• Dead match branches are not introduced.